Hard QCD probes to quark-gluon plasma

Abstract

Completely unexplored regimes of QCD, dominated by high-density/temperature effects, are available in heavy ion experiments at collider energies. The successful RHIC program shows how relevant the high transverse momentum part of the spectrum is for the characterization of the properties of the created medium. It points, as well, to interesting properties of the nuclear wave function at small fraction of momentum x, probably dominated by saturated color fields. In both domains, the imminent LHC program will provide a phase space enlarged by orders of magnitude with respect to those studied at RHIC. I will review the present status of hard probes in heavy ion collisions as well as the expectations for the LHC.